Determination of five priority haloacetic acids by capillary electrophoresis with contactless conductivity detection and solid phase extraction preconcentration

摘要

A sensitive capillary electrophoretic separation method with contactless conductivity detection (C4D) for analysis of five priority haloacetic acids (HAA5) is presented. The analytes were baseline separated in an electrolyte composed of 20 mM 2-(N-Morpholino) ethanesulfonic acid (MES), 20 mM L-histidine (HIS), and 30 μM cetyltrimethylammonium bromide (CTAB) at pH 6.0 in less than 4 min. A simplified solid-phase extraction (SPE) preconcentration procedure on highly cross-linked polystyrene-divinylbenzene (PS-DVB) type sorbent was developed and optimized with respect to short preconcentration time. HAA5 from a 25-mL sample aliquot of tap and swimming pool water could be preconcentrated in less than 5 min using an in-house made SPE column with recoveries ranging from 23 to 98%. Combining the SPE preconcentration procedure with capillary electrophoretic analysis, the attained limits of detection were between 6.1 and 12.2 μg/L with total analysis time of less than 10 min.